Romaine lettuce implicated in multistate E coli outbreak

May 6, 2010 (CIDRAP News) – Freshway Foods, based in Sidney, Ohio, today recalled some of its romaine lettuce products after a New York state laboratory assisting with the investigation of a multistate Escherichia coli O145 outbreak found the pathogen in an unopened product sample.

The US Food and Drug Administration (FDA) said today in a press release that so far 19 confirmed E coli O145 illnesses have been reported in Michigan, Ohio, and New York. The total is up by 4 cases since May 3, and other suspected cases are awaiting confirmation. Twelve of the patients have been hospitalized, including three with hemolytic uremic syndrome (HUS), a potentially fatal kidney complication.

Though the Centers for Disease Control and Prevention (CDC) is not the lead agency in the investigation, it is supporting the probe and is facilitating information-sharing between all the public health agencies taking part. The CDC said in an e-mailed press release that 10 more probable cases are related to the outbreak: 3 in Michigan, 5 in New York, and 2 in Ohio. It said the illnesses began between Apr 10 and 26. The median age range of patients sickened in the outbreak is 19 years, ranging from 13 to 29, and 69% of the patients are male.

The FDA said it supports Freshway's recall action and noted that the outbreak is still under investigation.

Today's recall affects only products sold under the Freshway and Imperial Sysco brands to food service outlets, wholesale customers, and in-store retail salad bars and delis. The company said it does not produce bulk prepackaged romaine or bagged salads containing romaine for sale in supermarkets. The recall applies only to produce with a use-by date of May 12 or earlier.

The products were distributed in 23 states east of the Mississippi River and the District of Columbia, including the three that have so far reported human cases. Freshway said the recalled romaine products were sold for in-store salad bars and delis in Kroger, Giant Eagle, Ingles Markets, and Marsh stores in the 23 states. The FDA said Freshway is advising consumers not to eat "grab and go" salads sold through those four grocery chain salad bars and delis.

On the recall list are 49 Freshway products and 23 Imperial Sysco products, which range from chopped romaine and lettuce mixes to an array of flavored salad kits such as Caesar and Oriental.

Freshway said in its recall notice that it is cooperating with the FDA and other public health investigators. It said so far an extensive investigation of the Freshway Foods facility in Sidney has found no evidence of contamination.

Phil Gilardi, president of Freshway Foods, said in the press release that the company has strict guidelines to ensure that its products are as safe as possible and will continue to seek ways to improve. "We are voluntarily issuing this recall, because we want to do everything possible to minimize risk to public health," he said.

Health officials have not yet definitely matched the outbreak strain with the E coli O145 strain found in the lettuce sample through DNA fingerprinting, but early case-control study findings in one of the three states shows a significant association between the romaine and the sick patients, according to the FDA. The FDA said preliminary traceback findings suggest that shredded romaine lettuce consumed by case-patients in Michigan, New York, and Ohio originated from a single processing facility.

The CDC said there are limited surveillance data on illnesses involving non-O157 serotypes of Shiga toxin-producing E coli (STEC), including O145. "Therefore E coli O145 may go unreported. Because it is more difficult to identify than E. coli O157, many clinical laboratories do not test for non-O157 STEC infection," it said in the press release.

Craig Hedberg, PhD, a food safety expert at the University of Minnesota in Minneapolis, told CIDRAP News that the outbreak is similar to E coli O157:H7 outbreaks that have previously been linked to lettuce. E coli O145 has been associated with cattle, like O157 and other STEC strains. "And it seems likely that cattle would have been the reservoir source of contamination for this outbreak as well," he said. "Of course, since the production source has not been identified, this is all speculation on my part, but it seems likely."

He also predicted that the E coli O145 outbreak will boost the urgency of calls to subject all STEC to the same regulations that apply to E coli O157:H7. "For products like lettuce, this may be a reasonable approach. However, not all STEC are equally pathogenic, and not all present the same public health threat," he said.

The issue is critical to products such as ground beef, he added. Because cattle are reservoir hosts to a variety of STEC, not all of which are pathogenic, it may be counterproductive to attempt to regulate all STEC as adulterants of ground beef. "It seems prudent to identify strains with particular virulence properties (such as Stx2 [shiga toxin type 2] subtype) associated with hemorrhagic colitis and HUS, and focus on those strains," he said.

At least one food safety group was quick to pounce on news of the lettuce recall. Caroline Smith DeWaal, food safety director for the Center for Science in the Public Interest (CSPI), said in a statement today that lettuce has once again been linked to an E coli outbreak, which should add urgency to US Senate consideration of the proposed Food Safety Modernization Act.

"While consumers wait for Congress to pass food safety legislation, the plants that process and bag lettuce and the farms that grow it are operating under an industry honor system which clearly failed in this case," she stated. "The FDA can’t tell us when it last had inspectors in the plant where this lettuce was processed. Congress urgently needs to give the FDA the resources and authority from the farm forward, transforming it from a reactive agency to an agency focused on preventing contamination."

See also:

May 6 FDA press release

May 6 CSPI statement

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